Compressor assembly having electronics cooling system and method

ABSTRACT

A refrigeration system having a compressor, a condenser, an evaporator, an accumulator, and electronics for controlling the compressor. The accumulator collects gaseous and liquid refrigerant passing from the evaporator to the compressor. The electronics are mounted to the accumulator to transfer heat from the electronics to the refrigerant located within the accumulator to cool the electronics.

FIELD

The present disclosure relates to a refrigeration system having variouselectronic components that may be cooled using refrigerant from therefrigeration system.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

A compressor may use electronics to control the compressor motor, tomodulate compressor capacity, to monitor various electrical systems ofthe compressor, and the like. During operation, however, the electronicsmay generate heat. If too much heat is generated, the electronics mayoverheat and fail.

SUMMARY

A system including a compressor, an accumulator in communication withthe compressor and having refrigerant located therein, and compressorelectronics mounted to the accumulator and cooled by the refrigerantlocated therein.

The electronics may be mounted to a bottom surface of the accumulator.

The electronics may be mounted to circumferentially surround theaccumulator.

The electronics may be housed by an annular housing thatcircumferentially surrounds the accumulator.

The accumulator may be an annular-shaped housing defining a cylinder,and the electronics may be mounted in the cylinder.

The electronics may be mounted within the accumulator.

The accumulator may include a base and a cylindrical housing having aflattened surface attached to the base, with the electronics beingmounted to the flattened surface.

The compressor electronics may include an inverter.

A system may also include a compressor, a high pressure zone heatexchanger and a low pressure zone heat exchanger in communication withthe compressor, an accumulator disposed between the low pressure zoneheat exchanger and the compressor that receives low temperaturerefrigerant from the low pressure zone heat exchanger, and compressorelectronics mounted to the accumulator and cooled by the low temperaturerefrigerant located therein.

The electronics may be mounted to a bottom surface of the accumulator.

The electronics may be mounted to circumferentially surround theaccumulator.

The electronics may be housed by an annular housing thatcircumferentially surrounds the accumulator.

The accumulator may be an annular-shaped housing defining a cylinder,and the electronics may be mounted in the cylinder.

The electronics may be mounted within the accumulator.

The accumulator may include a base and a cylindrical housing having aflattened surface attached to the base, with the electronics beingmounted to the flattened surface.

Heat generated by the electronics may be transferred to the lowtemperature refrigerant in the accumulator.

The compressor electronics may include an inverter.

A refrigeration system includes a compressor for compressing arefrigerant, a first heat exchanger in communication with the compressorfor condensing the refrigerant, and a second heat exchanger incommunication with the compressor for expanding the refrigerant. Anaccumulator may be disposed between the second heat exchanger and thecompressor. Compressor electronics may be mounted to the accumulator andcooled by the refrigerant that is expanded by the second heat exchanger.

The electronics may be mounted to a bottom surface of the accumulator.

The electronics may be mounted to circumferentially surround theaccumulator.

The electronics may be housed by an annular housing thatcircumferentially surrounds the accumulator.

The accumulator may be an annular-shaped housing defining a cylinder,and the electronics may be mounted in the cylinder.

The electronics may be mounted within the accumulator.

The accumulator may include a base and a cylindrical housing having aflattened surface attached to the base, with the electronics beingmounted to the flattened surface.

The compressor electronics may include an inverter.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a schematic representation of an exemplary refrigerationsystem;

FIG. 2 is a cross-sectional view of an accumulator having electronicsmounted thereto;

FIG. 3 is a cross-sectional view of an accumulator having electronicsmounted thereto;

FIG. 4 is a cross-sectional view of an accumulator having electronicsmounted thereto;

FIG. 5 is a cross-sectional view of an accumulator having electronicsmounted thereto; and

FIG. 6 is a cross-sectional view of an accumulator having electronicsmounted thereto.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

FIG. 1 is a schematic illustration of an exemplary refrigeration system10. Refrigeration system 10 may generally include a compressor 12, acondenser 14, an evaporator 16, and a system accumulator 18. Disposedbetween condenser 14 and evaporator 16 may be a restricted orifice orexpansion valve 20.

Refrigeration system 10 uses the cooling effect of evaporation to lowerthe temperature of the surroundings near one heat exchanger (i.e., theevaporator 16) and it uses the heating effect of high pressure, hightemperature gas to raise the temperature of the surroundings nearanother heat exchanger (i.e., the condenser 14). This is generallyaccomplished by releasing a refrigerant under pressure (usually in theliquid phase) into a low pressure region to cause the refrigerant toexpand into a low temperature mixture of liquid and vapor. Commonly,this low pressure region comprises an evaporator coil 22, that may beformed in the evaporator 16. Once in the evaporator coil 22, therefrigerant mixture may be exposed to high temperature ambient air ofthe region desired to be cooled. Evaporation of refrigerant from liquidto gas absorbs heat from the ambient air and thereby cools it.

Release of refrigerant into the low pressure evaporator coil 22 isusually metered by expansion valve 20. There are a wide variety ofdifferent types of restricted orifices and expansion valves in usetoday, ranging from simple non-adjustable capillary tubes toelectrically adjustable valves, such as pulse width modulated valves andstepper motor valves.

The refrigerant released by evaporator 16 may be compressed back into ahigh pressure state by compressor 12 and may be condensed into a liquidphase by condenser 14 so that it may be used again. In some systems,compressor 12 may be variable speed or variable capacity, so thatcompressor 12 also controls the rate at which refrigerant flows throughthe restricted orifice or expansion valve 20. Compressor 12 may be ascroll compressor, a vane compressor, a piston compressor, or any othertype of compressor known to one skilled in the art.

Accumulator 18 may be located between evaporator 16 and compressor 12,near a suction inlet (not shown) of compressor 12. Accumulator 18 maycapture excess liquid refrigerant in system 10 before it is allowed toreach compressor 12. If an excess of liquid refrigerant reachescompressor 12 it may damage bearings and other surfaces withincompressor 12 and cause compressor 12 to fail.

As stated above, compressor 12 may be a variable speed or variablecapacity compressor. Additionally, compressor 12 may include variousdiagnostic and protection systems. To vary the speed and/or the capacityof compressor 12, as well as run the diagnostic and protection systems,various electronic components 24 for control, diagnosis, and protectionof the of compressor 12 may be used. Electronic components 24 mayinclude various devices such as an inverter, controller, the protectionsystem, and the diagnostic system.

Electronic inverter, which may also be referred to as a variablefrequency drive (VFD), receives electrical power from a power supply anddelivers electrical power to compressor 12. By modulating the frequencyof electrical power delivered to the electric motor of compressor 12,inverter may thereby modulate and control the speed, and consequentlythe capacity, of compressor 12. To modulate the frequency of electricpower, inverter may include solid state electronics to modulate thefrequency of electrical power. Generally, inverter more specificallycomprises a converter that converts the inputted electrical power fromAC to DC, and then inverter converts the electrical power from DC backto AC at a desired frequency.

A controller such as Assignee's U.S. Pat. No. 6,302,654, which is herebyincorporated by reference in its entirety, may control compressorcapacity or monitor operating conditions of the compressor. Thecontroller may generally include a control block, memoryanalog-to-digital converters, a communication interface, and a pluralityof terminals connected to various sensors that monitor parameters of thecompressor. The control block, which includes processing circuitry, maycontrol compressor capacity. The analog-to-digital converter may be usedto convert analog signals sent by the various sensors to a digitalsignal before input into the controller. The communication interface mayprovide communication with the control block from an outside source orserver via, for example, an internet or intranet connection.

The compressor protection or diagnostic system may include a controller,such as that described above, and a power interruption system. Theprocessing circuitry of the diagnostic system is monitored by aplurality of sensors, and diagnoses operating conditions and faultsunder both normal and abnormal fault conditions by receiving andanalyzing motor, compressor, and system parameters. The processingcircuitry diagnoses conditions of the motor, compressor, or system byanalyzing trends and relationships among sensed data. In addition, thediagnostic data may be used to control compressor modulation based onsystem conditions detected by the sensors or faults determined by theprocessing circuitry.

The sensors generally provide diagnostics related to compressormechanical failures, motor failures, and electrical component failuressuch as missing phase, reverse phase, motor winding current imbalance,open circuit, low voltage, locked rotor currents, excessive motorwinding temperature, welded or open contractors, and short cycling. Thesensors may also monitor compressor current and voltage to determine,and differentiate between, mechanical failures, motor failures, andelectrical component failures. In addition, the sensors may monitorparameters such as discharge temperature, suction and dischargepressure, oil levels, vibration, capacity control, oil injection, andliquid injection. Exemplary compressor protection and control diagnosticsystems are described in the assignee's commonly owned U.S. patentapplication Ser. No. 11/059,646 filed on Feb. 16, 2005, and U.S. Pat.No. 6,615,594 which are hereby incorporated by reference in theirentirety.

As the above compressor electronics 24 operate, heat will be generated.If too much heat is generated, however, compressor electronics 24 mayoverheat. If compressor electronics 24 overheat, they could fail, therefrigeration system 10 may shut down, or may be forced reduce capacityto allow compressor electronics 24 to cool. Therefore providing a meansof cooling the electronics is desired.

Accumulator 18 may be disposed between evaporator 16 and compressor 12.Accumulator 18, therefore, may be disposed in the low pressure and lowtemperature region of refrigeration system 10. In this regard,accumulator 18 may have a temperature that may be close to that of thegaseous and liquid refrigerant located therein. Because accumulator 18may have a lower temperature relative to other elements of refrigerationsystem 10, the gaseous and liquid refrigerant located therein may beused to cool compressor electronics 24 by mounting compressorelectronics 24 to accumulator 18.

FIG. 2 illustrates a configuration where accumulator 18 may havecompressor electronics 24 mounted thereto. Accumulator 18 may be agenerally cylindrical housing including an inlet pipe 26 incommunication with evaporator 16 and a discharge pipe 28 incommunication with compressor 12. An outer surface 30 of accumulator 18may be flattened to allow for electronics 24 to be mounted thereto.

By mounting compressor electronics 24 to accumulator 18, heat 32 may betransferred through a wall 34 of accumulator 18 to the excess liquid andgaseous refrigerant located in accumulator 18. Transfer of heat 32 tothe refrigerant cools compressor electronics 24, which assists inpreventing compressor electronics 24 from overheating.

Accumulator 18 may be formed of any material that may transfer heat 32from compressor electronics 24 to the refrigerant liquid and gas. Inthis regard, the material selected for accumulator 18 may be a metalmaterial such as a draw-quality or spin-forming-quality steel. Stainlesssteel may be used in high pressure applications and, aluminum and coppermay be also used. Regardless which material is selected, the materialshould be able to withstand storage of the liquid and gaseousrefrigerant, as well as withstand system pressures.

FIG. 3 illustrates a configuration where compressor electronics 24 maybe mounted to a bottom surface 36 of accumulator 18. In contrast to theabove configuration where compressor electronics 24 are mounted to wall34 of accumulator 18 and heat may be transferred to both the liquid andgaseous refrigerant located in accumulator 18, bottom surface 36 ofaccumulator 18 generally only has contact with liquid refrigerant (ifpresent), which generally may have a lower temperature than the gaseousrefrigerant. By mounting compressor electronics 24 to bottom surface 36,therefore, compressor electronics 24 may be in contact with a surface ofaccumulator 18 that has a lower temperature. Because bottom surface 36may have a lower temperature relative to other regions of accumulator18, cooling of compressor electronics 24 may be further enhanced.Moreover, only a minimum amount of liquid refrigerant may be present inaccumulator 18 to subject compressor electronics 24 to a higher amountof energy transfer between compressor electronics 24 and bottom surface36 of accumulator 18.

Now referring to FIG. 4, compressor electronics 24 may have an annularhousing 38 mounted to surround accumulator 18. Mounting compressorelectronics 24 circumferentially around accumulator 18 increases thesurface area between compressor electronics 24 and accumulator 18. Byincreasing the surface area between compressor electronics 24 andaccumulator 18, a larger amount of heat 32 may be transferred betweencompressor electronics 24 and the gaseous and liquid refrigerant locatedwithin accumulator 18 to further cool compressor electronics.

FIG. 5 illustrates a configuration where accumulator 18 may beannular-shaped cylinder 40 having an aperture 42 formed therein.Compressor electronics 24 may be housed within aperture 42. Similar tothe configuration where compressor electronics 24 circumferentiallysurround accumulator 18, mounting compressor electronics 24 in aperture42 increases the surface area between compressor electronics 24 andaccumulator 18. By increasing the surface area between compressorelectronics 24 and accumulator 18, a larger amount of heat 32 may betransferred between compressor electronics 24 and the gaseous and liquidrefrigerant located within accumulator 18 to further cool compressorelectronics. Moreover, when accumulator 18 surrounds compressorelectronics 24, accumulator 18 may act as an electromagnetic shield forcompressor electronics 24.

Now referring to FIG. 6, compressor electronics 24 may be mounted withinaccumulator 18. Mounting compressor electronics 24 within accumulator 18provides the greatest amount of cooling for compressor electronics dueto compressor electronics 24 being in direct contact with therefrigerant. To provide electrical connections between compressor 12 andcompressor electronics 24, accumulator may be provided with hermeticterminals (not shown) that allow for electrical communication betweencompressor 12 and compressor electronics 24. Furthermore, compressorelectronics 24 should be disposed in a housing 44 able to withstandexposure to the liquid and gaseous refrigerant. Regardless, byincreasing the surface area between compressor electronics 24 andrefrigerant located within accumulator 18, a larger amount of heat 32may be transferred between compressor electronics 24 and the gaseous andliquid refrigerant located within accumulator 18 to further coolcompressor electronics. Moreover, when accumulator 18 surroundscompressor electronics 24, accumulator 18 may act as an electromagneticshield for compressor electronics 24.

The above detailed description is merely exemplary in nature and, thus,variations that do not depart from the gist of the present teachings areintended to be within the scope of the present teachings. Suchvariations are not to be regarded as a departure from the spirit andscope of the present teachings.

1. A system comprising: a compressor; an accumulator in communicationwith said compressor and having refrigerant located therein; andcompressor electronics mounted to said accumulator and cooled by saidrefrigerant located therein.
 2. The system of claim 1, wherein saidelectronics are mounted to a bottom surface of said accumulator.
 3. Thesystem of claim 1, wherein said electronics are mounted tocircumferentially surround said accumulator.
 4. The system of claim 3,wherein said electronics are housed by an annular housing thatcircumferentially surrounds said accumulator.
 5. The system of claim 1,wherein said accumulator is an annular-shaped housing defining acylinder, and said electronics are mounted in said cylinder.
 6. Thesystem of claim 1, wherein said electronics are mounted within saidaccumulator.
 7. The system of claim 1, wherein said accumulator includesa base and a cylindrical housing having a flattened surface attached tosaid base, said electronics being mounted to said flattened surface. 8.The system of claim 1, wherein said compressor electronics includes aninverter.
 9. A system comprising: a compressor; a high pressure zoneheat exchanger and a low pressure zone heat exchanger in communicationwith said compressor; an accumulator disposed between said low pressurezone heat exchanger and said compressor that receives low temperaturerefrigerant from said low pressure zone heat exchanger; and compressorelectronics mounted to said accumulator and cooled by said lowtemperature refrigerant located therein.
 10. The system of claim 9,wherein said electronics are mounted to a bottom surface of saidaccumulator.
 11. The system of claim 9, wherein said electronics aremounted to circumferentially surround said accumulator.
 12. The systemof claim 11, wherein said electronics are housed by an annular housingthat circumferentially surrounds said accumulator.
 13. The system ofclaim 9, wherein said accumulator is an annular-shaped housing defininga cylinder, and said electronics are mounted in said cylinder.
 14. Thesystem of claim 9, wherein said electronics are mounted within saidaccumulator.
 15. The system of claim 9, wherein said accumulatorincludes a base and a cylindrical housing having a flattened surfaceattached to said base, said electronics being mounted to said flattenedsurface.
 16. The system of claim 9, wherein heat generated by saidelectronics is transferred to said low temperature refrigerant in saidaccumulator.
 17. The system of claim 9, wherein said compressorelectronics includes an inverter.
 18. A refrigeration system comprising:a compressor for compressing a refrigerant; a first heat exchanger incommunication with said compressor for condensing said refrigerant; asecond heat exchanger in communication with said compressor forexpanding said refrigerant; an accumulator disposed between said secondheat exchanger and said compressor; and compressor electronics mountedto said accumulator and cooled by said refrigerant that is expanded bysaid second heat exchanger.
 19. The system of claim 18, wherein saidelectronics are mounted to a bottom surface of said accumulator.
 20. Thesystem of claim 18, wherein said electronics are mounted tocircumferentially surround said accumulator.
 21. The system of claim 20,wherein said electronics are housed by an annular housing thatcircumferentially surrounds said accumulator.
 22. The system of claim18, wherein said accumulator is an annular-shaped housing defining acylinder, and said electronics are mounted in said cylinder.
 23. Thesystem of claim 18, wherein said electronics are mounted within saidaccumulator.
 23. The system of claim 18, wherein said accumulatorincludes a base and a cylindrical housing having a flattened surfaceattached to said base, said electronics being mounted to said flattenedsurface.
 24. The system of claim 18, wherein said compressor electronicsincludes an inverter.